Why it's important to get to bed early

Late sleep times have been linked to poor eating and exercise habits.

With the hectic nature of modern living, for many of us it seems like a miracle to squeeze in six hours of sleep a night.

But it's not just about how much sleep you get but when you hit the hay each night, according to results of a new study conducted by a team at Northwestern University in Chicago, Illinois.

The researchers looked at a group of 96 healthy adults between the ages of 18 and 50 who regularly got at least six and a half hours of sleep. Over a seven day period, they tracked the duration and quality of sleep using wrist monitors as well as overall calorie intake, food choices, and physical activity. Interestingly, the researchers found that delaying the sleep schedule, that is, getting to bed later, led to some poor effects on the health of the participants, regardless of the total amount of sleep they had. In the study, participants who went to bed late ate more fast food and consumed fewer vegetables than those who went to bed earlier. They also had lower levels of physical activity.

The participants ended up consuming about the same amount of calories overall, with those who made a habit of late sleep schedules actually tending to have lower BMIs. However, the quality of the calories consumed was much worse for those who went to bed at the later time.

"Our results help us further understand how sleep timing in addition to duration may affect obesity risk," said principal investigator Dr Kelly Glazer Baron. "It is possible that poor dietary behaviours may predispose individuals with late sleep to increased risk of weight gain."